CVE-2026-101310 FreeBSD CVE debrief

Who should care

Defenders managing virtualized environments using bhyve on FreeBSD should assess exposure and prioritize patching. Roles include security teams, system administrators, and virtualization infrastructure managers.

Why it matters

CVE-2026-101310 is a high-severity vulnerability in the HDA audio device model used by bhyve on FreeBSD. It allows for potential out-of-bounds read or write and could lead to denial of service or code execution in the host userspace context. Defenders should prioritize patching and verifying vulnerability remediation, especially in environments running untrusted guests.

• Potential for guest-to-host escalation
• Risk of bhyve process crashes leading to denial of service
• Need for verification of patch application and vulnerability remediation
• Potential for code execution in host userspace context

Technical summary

The HDA audio device model did not check for zero-length Buffer Descriptor List (BDL) entries when starting a stream, leading to potential out-of-bounds read or write during DMA transfer processing. BDL fields were also subject to modification by the guest after validation. A malicious guest can crash the bhyve process or potentially execute arbitrary code in the host userspace context running the virtual machine, subject to bhyve's Capsicum sandbox.

Defensive priority

Defenders should prioritize verifying and applying patches for bhyve, especially in environments where untrusted guests are run.

Recommended defensive actions

• Verify and apply patches for bhyve
• Review and update vulnerability management processes
• Monitor for potential exploitation attempts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its CVSS score and potential impacts. A reference from FreeBSD's security advisory provides additional context. Defenders should verify patch application, review vulnerability management processes, and monitor for potential exploitation attempts. The vulnerability allows for potential out-of-bounds read or write and could lead to denial of service or code execution in the host userspace context. Evidence is limited to public sources and may not reflect all un

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.